Episode Transcript
Welcome to Faith and Science. I'm Dr. John Ashton.
I remember reading Darwin's work on evolution, Charles Darwin's work on evolution. And one of the doubts that he had was how the human eye could have evolved. And of course, now, more than 150 years since Darwin's book was published, and we have so much more information about the human eye.
But yet it's interesting that in evolutionary circles and in the sort of creation evolution debate, some professors have actually argued that the eye is evidence for evolution and against intelligent design. So I thought it'd be interesting to look at this. And I found an interesting article that you can look up on the web if you google.
Is the human eye really evidence against intelligent design? It's by Jonathan Wells, and he actually has two PhDs, one in molecular and cell biology from the University of California, Berkeley. Now, that's one of the top campuses of the University of California, and he also has one in a PhD in religious studies from Yale University.
So he's taught biology at California State University in Hayward and has worked in medical laboratory work for some time.
But this article, “Is the Human Eye Really Evidence Against Intelligent Design?” was published back on the 13 April, back in 2018. So he starts off by looking at the statement that some people argue that the human eye is flawed and therefore proving that it can't be intelligently designed or designed by God, because we wouldn't expect God to design something was flawed, and points out that vertebrates or animals with backbones, such as humans and cephalopods, they're sort of like squids and octopuses, have what are called camera eyes. And so these are roughly spherical with the lenses that focus images on the light sensitive retinas at the back of the eye.
So the light sensing cells actually point towards the back of the retina. And the lure nerve cells that transmit the signals to the brain are between the light sensing cells and the incoming light. Now, that's in sort of human eyes and other vertebrate eyes, but in contrast, cephalopod eyes or the octopus eyes, the light sensing cells point towards incoming light, and the nerve cells are at the back.
So there's a little bit of difference there. But it's interesting, back in 1986, the sort of ardent evolutionist and atheist Richard Dawkins published a best selling book called, “The Blind Watchmaker: Why the Evidence of Evolution Reveals a Universe Without Design”. And so The Blind Watchmaker book was very popular, and in it, Dawkins uses the vertebrate eye as evidence against design.
And what he wrote was, any engineer would naturally assume that the photocells would point towards the light with their wires leading backwards towards the brain. He would laugh at any suggestion that the photocells might point away from the light with their wires departing on the side nearest the light. Yet this is exactly what happens in all vertebrate retinas.
Each photocell is, in effect, wired backwards, with its wire sticking out on the side nearest the light. The wire has to travel over the surface of the retina to a point where it dives through a hole in the retina, the so called blind spot, to join the optic nerve. Well, that's what Dawkins wrote, and so we know that eyes work reasonably well.
And Dawkins concedes this. But what he argues is that it's the principle of the thing which would offend, and to use his word, any tidy minded engineer.
Now, it's interesting. Another biologist, some years later, George Williams, wrote there would be no blind spot if the vertebrae eyes were intelligently designed. In other words, if they were rearranged so that those wires didn't have to go through the retina. And he goes on to point out that the retina of a squid sort of is the right way.
A few years later, again in 1994, another biology professor, Kenneth R. Miller, argues similarly that the human eye, which he mocked was supposed to be the paragon of intelligent design, is badly designed. And he says no one, for example, would suggest that the neural wiring connections should be placed on the side that faces the light rather than the side away from it. And he goes on, of course, incredibly, this is exactly how the human retina is constructed. By contrast, the cephalopods retina is wired the right side out.
Another one in 2005. So we can see there's this continual attack that hang on. The way the human eye is designed is sort of not the best design. It's clumsy. Why would you do that?
So in 2005, another scientist, Douglas Futuyma, published a textbook about evolution, claiming that no intelligent engineer would be expected to design the functional nonsensical arrangement, they're his words, of cells in the human retina.
Another sort of creationist, geneticist Jerry Coyne, wrote that “the human eye is certainly not the sort of eye an engineer would create from scratch.” Instead, “the whole system is like a car, in which all the wires to the dashboard hang inside the driver's compartment instead of being tucked out of sight, safely out of sight.” So you can see these scientists appear to be generating a case for why would God do this? But I think if we look at this, maybe we should ask that question, why would God do this? But these scientists, like Dawkins, Williams, Miller, Futuyma and Coyne, they attribute this design to unguided evolution. And so what they say is, you know the fact that there's these flaws, see, this is evidence for evolution. It can't have been guided by an intelligent being, because an intelligent being wouldn't have done this.
And of course, the 2014 biology textbook by Mason, Leos and Singer informs students that, and they state, for example, to quote them, “an excellent example of imperfect design is the eye of vertebrate animals, in which photoreceptors face backwards towards the wall of the eye. By contrast, the eyes in cephalopods are more optimally designed” and so it keeps on going. And there are another molecular biologist Nathan Lents, wrote similarly in 2015.
So from the perspective of evolutionary theory, these scientists are all claiming that the human eye is evidence for unguided evolution and against intelligent design.
So it's very interesting that we need to be aware that these sort of arguments are put up against intelligent design and in favour of evolution. But let's have a look at this a little bit more closely.
Is the human eye really evidence against design? And this is where this biologist, Jonathan Wells, makes some very interesting points. He points out that the light sensing cells in a vertima retina require a lot of nutrients and a vast amount of energy. And in mammals, they have the highest metabolic rate of any tissue in the body.
About three quarters of the blood supply to the eye flows through a dense network of capillaries called choreocapillaris, which is situated behind the retina. Oxygen and nutrients are transported from the chlorocapillaris to the light sensing cells by an immediate layer of cells, which are called the retinal pigment epithelium, or RPE. Now, in addition to transporting oxygen and nutrients to the light sensing cells, the retinal pigment ephemelium, the RPE performs two other essential functions.
Firstly, the dark pigment in it absorbs scattered light, improving the optical quality of the eye. Secondly, it removes toxic chemicals that are generated in the process of detecting light. The light sensing cells contain stacks of discs, and in 1967, Richard Young showed experimentally that a photoreceptor cell continually renews itself by shedding discs at the end closest to the retinal pigment epithelium, replacing them with newly synthesised discs at the other end.
Then the retinal pigment epithelium engulfs the shed discs and neutralises the toxins. So here we see that hang on detection of lies, not just about, just simple photocells, and that there's a whole lot more to this. And let's have a look more closely then, at what some of the requirements.
So Jonathan Wells goes on, blood is almost opaque, and the retinal pigment epithelium absorbs light. If the light sensing cells were to face the incoming light, the blood field chlorocapillaris and the retinal pigment epithelium would have to be in front of the retina, where they would block most or all of the light. By contrast, the nerve cells are comparatively transparent and they block very little of the incoming light because of the high metabolic requirements of light sensing cells and their need to regenerate themselves.
The inverted retina is actually much better than the tidy minded design imagined by evolutionary biologists. So here we see that actually there's very good reason, because vertebrates have this much higher metabolic rate and because of these other requirements for the eye, there's actually good reason for having the eye designed or created the way it is. Also, they point out, the blind spot is not a serious problem, because the blind spot produced by the left eye is not in the same place as the blind spot produced by the right eye.
This means that in humans with two good eyes, the field of vision of one eye covers for the blind spot of the other eye and vice versa. So that's very interesting. And I think, again, this is actual powerful evidence for design, because why would that just happen to randomly occur? You'd think that the right and left eye, if they'd evolved, would have evolved with the same sort of design.
But again, we can see that they have a different and complementary structure. And so what we see is that often in these claims that are put up against design, and they're superficial, and often evolutionary scientists get much more press, much more opportunity to present their ideas than creationist scientists. But we can see that there are very, very strong reasons that are coming out now for creation.
And so Jonathan Wells goes a little bit further and he says, well, what about the claim that cephalopod eyes are better than vertebrate eyes?
In 1984, a team of Italian biologists pointed out that the cephalopod eyes are physiologically inferior to vertebrate eyes. In vertebrate eyes the initial processing of visual images occurs in the retina by nerve cells right next to the photoreceptor cells. In cephalopod eyes nerve pulses from the photoreceptor cells must travel all the way to the brain to be processed so a cephalopod eye is just a passive retina, which is able to transmit only information dot by dot, coded in a far less sophisticated fashion than in vertebrates. The result is slower processing and fuzzier signals.
And so that was a very, very interesting result there, if people want to look up that reference. By the way, it was published in Developments in Ophthalmology, 1984, volume 9, pages 20-28. And the title of the article was, “The Advantages of an Inverted Retina.”
So remember, in humans we have an inverted retina, whereas in the cephalopods it's the right way. So this is very, very powerful evidence. By the way, if you google Jonathan Wells article again, it's titled, “Is the Human Eye Really Evidence Against Intelligent Design?” There are a whole lot of references there at the end to a number of the quotes that I've been reading.
So it's interesting that he points out that all the research cited above about the chlorocapillaris and the RPE and the superiority of vertebrate eyes to cephalopod eyes was published before Dawkins published the Blind Watchmaker. But Dawkins and the other critics of intelligent design didn't bother to cheque the scientific literature claims. They simply assumed that evolution is true and that they knew how an eye should be designed.
And then they concluded that the human eye is badly designed and claimed it's evidence for evolution, and ignored the contrary evidence. And I think this is another example of what is happening today. We have so much evidence today that evolution is absolutely impossible.
But again, the educationists in western society and western countries are continuing to push evolution through the education system. So our young people are growing up not knowing the overwhelming evidence that there is that evolution is absolutely impossible. And the more we delve deeper into the biology, the sciences of biology, and the more evidence we have of supernatural creation of all living things, the design involved in these organisms could not have arisen by random chance blind chemical mutations to the DNA molecule, which is what evolutionists claim.
In fact, another article that I was reading quite recently that was actually published a little bit earlier in January 2017, it was titled, “How the Origin of the Human Eye is Best Explained Through Intelligent Design”. And one of the things that I found fascinating in reading this article was that the human eye consists of over 2 million working parts, making it second only to the brain in complexity. Of course, when we look at some of the properties of the eye, we think really, again it points at it's absolutely impossible for this coordinated, amazing machine that converts photons into, with the help of our brain into visual images, photons, light striking the retina into images.
In our brain, the coordinated system between the eye, its structure and the brain is amazing. For example, the eyes have automatic focus. For a long time, cameras had to be focused manually, using the automatic focusing system.
In our own eyes, of course, they've developed automatic focusing now, but again, that took engineers and scientists and physicists to develop that system. But the lens of the eyes, suspended in position by hundreds of string like fibres called zonules, and the ciliary muscle, changes the shape of the lens as a result of this, and it relaxes to flatten the lens for distant vision, and then for close work, it contracts, rounding out the lens so that we can see and focus the objects that are close. This happens automatically and virtually instantaneously without you having to think about it.
And so again, one of the questions ask is, how could evolution produce a system that even knows when it is in focus, let alone develop the mechanism of focus? How could evolution produce a system that can control a muscle that is in the perfect place to change the shape of the lens? You see, when we delve into the detail of the design here, we find there's enormous challenges for such a system being produced by chance. And this is just the system to focus the automatic focusing system. Again we have this issue of how does it know, coupled to the brain, which way to pull the muscle so that it's focused.
Unless it works, unless that system is in place it's just not going to work, you're not going to see anything clearly. And then we have the visual system.
The retina is composed of photoreceptor cells. When light falls on one of these cells, it causes complex chemical reaction that sends an electrical signal, then through the optic nerve to the brain. And there's a whole lot of steps in that pathway, nine steps that are involved, and for the light to go all the way through.
And so if this pathway with all its steps did not happen to suddenly evolve, such a signal could not be sent and go all the way through. Again, even if that happened, how is the receptor cell going to know what to do with the signal? It will have to learn what the signal means. And again, the system that is used to interpret and process the signal involves a great many other programmes, proteins rather, that's unique to the system.
And so again, there's huge issues with just the visual system itself and the parts of the brain that are involved in this visual system.
And we see that different parts of the brain, of course, are involved in regulating different parts of the eye's operation. Again, all this requires amazing coordination between the eye as this visual machine and the brain itself.
It's interesting that each eye takes a slightly different picture of the world. And at part of the eye called the optic chiasm, each picture is divided in half. The outer left and right halves continue back towards the visual cortex.
The inner left and right halves cross over to the other side of the brain and then continue back to the visual cortex. And the images that is projected onto the retina, of course, is upside down. The brain flips the image back up the right way during processing.
And somehow the human brain makes sense of the electrical pulses receive via the optic nerve and translates those electrical pulses into visual images in our mind. This is amazing. And the author points out, how could natural selection recognise the problem needing to flip the image the right way up and evolve a mechanism of the left side of the brain receiving information from the left side of both eyes and the right side of the brain receiving information from the right side of both eyes? How could evolution produce a system that can interpret electrical impulses and process them into images? These are amazing issues that we just take for granted.
But to try and explain them by blind, random, chemical mutations to a code, we can see it just makes so much sense it's absolutely impossible for such a system that coordinates the physical light receiving system, the translation into electrical pulses and then the visual images that we get produced in our mind that are all coordinated, for that to arise by chance. But then there's more.
The retina needs a fairly constant level of light intensity to best form useful images with our eyes. And therefore we've got the iris muscles that control the size of the pupil. It contracts and expands, opening and closing the pupil in response to the brightness of the surrounding light.
Just as the aperture in a camera protects the film from overexposure, the iris of the eye helps protect the sensitive retina. How would evolution produce a light sensor? And even if evolution could produce a light sensor, how can a purely naturalistic process like evolution produce a system that knows how to measure light intensity?
And then, of course, we've got the detailed vision. The cone cells give us our detailed colour, daytime vision, and there's about 6 million of those. And again, the structure of these all has to be encoded.
Of course, for night vision, the rod cells give us our dim light or night vision, and they're 500 times more sensitive to light and also more sensitive to motion than cone cells. And so again, we have just lubrication, the lacrimal gland continually secretes tears, which moisten, lubricate and protect the surface of the eye and also protect it from infections. If there was no lubrication system, our eyes would dry up and cease to function within a few hours.
And then, of course, we've got eyelashes that protect the eyes from particles that may injure them and so forth.
And we have all the muscles. Six muscles are in charge of eye movement. Four of these move the eye up and down, left and right, and the other two control twisting motion of the eye when we tilt our head. Yeah.
There's so much to this design, when you think about it. The evolution says that random mutations has produced the structure for all these muscles in just the right place at just the right time, with just the right nerves that control them. I think we can see overall that the eye itself is overwhelming evidence for creation, not evolution, and that the evolutionists that have promoted the eye as evidence for evolution have not really understood what is involved and they've not really understood the evidence of the design, how the eye works.
And so, again, we have this evidence there that just isn't getting out to young people of the existence of a super intelligent creator God. The Bible tells us that this God is a loving creator God and who revealed himself through Jesus Christ. This evidence really needs to get out to people.
And I would like to really encourage listeners to put links to these programmes, put links to the books that promote the evidence for creation, such as this website and even the website creation.com. The information needs to get out there. We need to spread this around to young people that there's overwhelming evidence for the existence of a loving God that created our eyes to see the beautiful world around us.
Remember, if you want to relisten to this programme, just Google 3abnaustralia.org.au All one word and click on the radio and listen button.
I'm Dr. John Ashton. Have a great day. You've been listening to a production of 3ABN Australia radio.
